28797720 has 64 divisors (see below), whose sum is σ = 98737920. Its totient is φ = 6582144.

The previous prime is 28797719. The next prime is 28797721. The reversal of 28797720 is 2779782.

It is an interprime number because it is at equal distance from previous prime (28797719) and next prime (28797721).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28797721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16302 + ... + 17981.

It is an arithmetic number, because the mean of its divisors is an integer number (1542780).

Almost surely, 2^28797720 is an apocalyptic number.

28797720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28797720 is an abundant number, since it is smaller than the sum of its proper divisors (69940200).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28797720 is a wasteful number, since it uses less digits than its factorization.

28797720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34304 (or 34300 counting only the distinct ones).

The product of its (nonzero) digits is 98784, while the sum is 42.

The square root of 28797720 is about 5366.3507153372. The cubic root of 28797720 is about 306.5156839222.

The spelling of 28797720 in words is "twenty-eight million, seven hundred ninety-seven thousand, seven hundred twenty".